Tool joint



Oct. 25, 1949. J, MOON 2,485,763

TOOL JOINT Filed July 16, 1946 2 Sheets-Sheet 2 INVENTKOR. (IH/nfs MoQ/vgy@ i;

TTOKNEY Patented Oct. 25, 1949 TOOL JOINT .laines Moon, Altadena,Calif., assigner to Signal Oil and Gas Company, Los Angeles, Calif., a

corporation of Delaware Application July 16, 1946, Serial No. 684,022

4 Claims. (Cl. 285-174) This invention relates to a tool joint andcollar assembly which permits of ready assembly of strings of drill pipeemployed in drilling of bore holes in the earth for the production ofwater, oil, gas, and other fluids.

In prior drilling practice the drill string formed of sections of pipescrewed together by means of tool joints, the pipe could be rotated in aclockwise direction only. Reversal of rotation could not be effected. Inorder to permit of this reversal in rotation, it is necessary that thescrewed joints employed between the kelly, tubing sections, drillcollars, and bits do not unscrew on reversal of rotation. In presentpractice all screwed joints are either left or right-handed, that is,they tighten when the cutting part into the screwed joint is rotatedclockwise. With such screwed joints reversal of rotation of the drillpipe is impractical and dangerous, since there is a danger that thejoints will become unscrewed. This results from the fact that thefrictional resistance of the earth against the bit and the side Walls ofthe bore hole against the side of the tubing is Very large in drilling.In fact, substanu tially the entire. drilling load, running up to 100horsepower and more, is employed in overcoming the frictionalresistance. For this reason the conventional threaded couplings are madeup with considerable tension and are all of a hand to be tightenedduring rotation.

I have devised a tool joint which will be just as tightly assembledwhether the string is rotated clockwise or counter-clockwise. By sodoing, the forces which result from the rotation of the drill pipe whichcause drift and spiralling of the bore v are cancelled out, since byreversing the direction of rotation the direction of the forces isreversed, and thus the net result is to neutralize them and the borehole may traverse its predetermined course whether vertical, horizontal,or deviated.

I may, therefore, also employ the more iiexible drill pipe and shorterdrill collar assemblies required for drilling of deviated bore holes ofhigh angle and large degrees of curvatures and maintain the drill pipeon the whipstock. By reversing direction of rotation, the forces, whichon rotating in one direction cause the drill pipe to ride off the sidesof the Whipstock, will be neutralized and the drill pipe be maintainedin the whipstock and the drill pipe will feed off the end of thewhipstock. The reversal of rotation will also permit wear on both sidesof the teeth so that the bit life is prolonged and a greater amount ofdrilling between bit changes permitted.

This invention will be further described in connection with thedrawings, in which Fig. -1 is a quarter section of a drill pipe and tooljoint showing the joint before make-up;

Fig. 2 is a quarter section showing the joint made up;

Fig. 3 is a full section taken on the line 3-3 of Fig. 1;

Fig. 4 is a full section partly broken away, taken on the line 4-4 ofFig. 2;

Fig. 5 is a full section taken on the line 5 5 of Fig. 1;

Fig. 6 is a full section taken on the line 6-6 of Fig. 2; Fig. 7 is afragmentary quarter section of the joint showing an alternative lockingmeans with the sleeve excluded; and

Fig. 8 is similar to Fig. '7 showing the sleeve y in locked position.

The pin end 2 of the tool joint is suitably secured to the drill pipe bywelding the joint to the drill string. Such connection of tool jointsand drill strings is quite conventional. `Any other suitable means forconnecting the joint and the plpe may be employed. The pin 2 is formedwith circumferential shoulders 3 and 4. The shoulder 3 is positionednear the external ends of the pin 2. The outer surface of the pinbetween the shoulder 4 and the end l carries splines 6. I

The box end 8 of the tool joint is connected to the drill pipe in amanner similar to the connection of the pin end 2. The box has formedtherein an external shoulder 9 and shoulder I2, and internal groove I0.Between groove I0 and shoulder I2 are splines II complementary to thesplines 6.

The box 8, beyond the shoulder I2, is formed integrally with or joinedby welding to a series of spring fingers I3 which are circumferentiallyspaced from each other, as shown in Figs. 3, 4, and 6, and placed at theend of the solid section of the box. In their normalr position the ngersstand away from the box, i. e., are bowed away from the axis of saidbox, as shown in Fig. l. Each finger I3 is formed with an internalshoulder I4 which forms an overhanging lip at the free end of thefingers. These lips are complementary to the external shoulder 3.

An outer sleeve I6 is slidably positioned on the outside of the box 8and carries an internal groove Il into which a split lock washer I8 maybe placed. The sleeve is formed with a series of grooves I9 which tslidably over the fingers I3 and with lips lila which nt between thespaced fingers, as shown in Figsl, 2, and 4. A groove 20 3 is positionednear the end of the sleeve I6 to receive a split washer 2i similar toI8. The collar I6 is retracted to the position shown in Fig. 1.

The tool joint may be assembled as follows: With the pin end removed, aU-shaped circular packer |8a is placed in the groove l0. The packingring 5 is placed in the shoulder d. The pin is inserted into the boxwith the splines 6 mating with the splines I l. The sleeve I6 is thenpushed over the fingers I3, compressing them so that the slopingshoulder il engages the sloping shoulder 3. When the sleeve has beenpushed home the ring i8 abuts the shoulder il and the groove 20overhangs the end i5. The split ring 2l is then introduced into thegroove 20 and thesleeve is thus locked in place.

In order to hold the sleeve in unlocked position, as shown in Fig. 1, Imay provide a lock such as Ishown The ball 28 positioned in the bore 21on spring 26 may engage a detent 29 to hold the sleeve in such openposition.

A second detent 30 may also be provided so that when the pin isdisengaged from the box, the sleeve may be slid over the iinger l5 andlocked in place by engagement of detent 30 with ball 29 to cover andguard the spring fingers against damage. This will permit of placing thebox on a iioor such as is usual when stacking drill pipe.

Figs. 7 and 8 show a sleeve locking means which is alternative to thesplit ring 2l. Certain or all of the ngers carry a bore 22 in which ispositioned a spring 23 and a ball 24. The sleevc I6 has formed therein acomplementary detent 25. When the sleeve is pushed into locking positionthe ball 2d enters the detent 25 to lock the sleeve against displacementby any force to be encountered in the use of the drill string. Byexerting a larger force, the sleeve may be slid over the ball which wasforced into the bore 23 against the spring 22. The detents 30 and 29 andthe ball 28 may also be employed in this form. `When the box isdisengaged from the pin the sleeve mayv also, in this form, be slid overthe spring fingers and locked in place by means oi the ball 2li or ball29- As Will be seen this tool joint has no threads for locking thejoints and may be assembled simply by sliding the box over the pin andpushing the locking sleeve into position. No rotation of the drillstring is thus necessary to make up the drill string, thus avoiding anoperation now generally employed and which has caused numerousaccidents. Additionally, the drill string may be rotated eitherclockwise or counter-clockwise or rotation may be reversed periodicallyduring drilling without danger of separation of the drill string at thetool joints. When the sleeve I6 is slid over the spring iingers, asshown in Fig. 2, the lateral displacement of the sleeve is prevented bythe lock washers I8 and 2| or the lock 25. The lateral separation of thebox and pin is prevented by the engagement of the shoulder ld of thespring fingers with the shoulder on the pin 2.

This same construction may also be used not only between the drill pipesections, but to connect the drill pipe to the kelly, or to the drillcollars, or to connect drill collars together, or to connect the drillcollar to the drill, or connect the kelly to the swivel to make up anentire drill string which could be rotated either clockwise orcounter-clockwise.

While I have described a particular embodiment of my invention for thepurpose of illustration, it should be understood that Variousmodications and adaptations thereof may be made the appended claims.

I claim: v

1.A A drill collar, comprising a pin portion, 9X-- ternal splines at theend of the pin, external splines on said pin, a. box portion, internalsplines on said box portion complementary t0 the eX- ternal splines onsaid pin portion, a plurality of spring ngers mounted on said box. asleeve slidably mounted over the exterior surfaces of said box and saidspring fingers, and means for engaging said spring ngers with said pinto lock said box and pin when said sleeve is slid over said springiingers to prevent lateral separation of said box and pin, said meansincluding means for locking said sleeve in position over said springlingers, said locking means also including circumferential locking meansto lock said sleeve in position irrespective of the angular position ofsaid sleeve with respect to said fingers, said locking means beingoperative to prevent lateral displacement of said sleeve.

2. A drill collar, comprisinga pin portion, external splines at the endof the pin, external splines on said pin, an internal shoulder near theend of said pin, a box portion, internal splines on said box portioncomplementary to the external splines on -said pin portion, a pluralityof spring Iingers mounted on said box, said spring fingers beingnormally bowed away from the axis of said box, an overhang-ing lipformed at the free end of said spring fingers complementary to saidexternal shoulder on said pin, a sleeve slidably mounted over theexterior surfaces of said box and said spring iingers, said4 springfingers being forced into a position along the exterior surface of saidpin and engaging the lip of said spring ngers with said externalshoulder, and means for locking said sleeve in position to hold saidspring ngers in said last-named position and to hold said lips inengagement with` said exterior shoulders to prevent lateral separationof said vbox and pin.

3. A drill collar, comprising a pin portion and a box portion, anexternal shoulder on said pin portion, a second external shouldermounted on said pin portion longitudinally spaced from said firstmentioned external shoulder on said pin portion, lan internal sealpositioned on the wall of said box section and abutting the end of saidpin, an internal shoulder on said box section, a seal between saidlast-named shoulder on the box and the iirst-named shoulder on said pinsection, a plurality of spring iingers mounted on said box, said springlingers being normally bowed away from the axis of said box, anoverhanging lip formed at the free end of said spring lingerscomplementary to said second external shoulder on said pin, a sleeveslidably mounted over the exterior surfaces of said box and said springfingers, said spring fingers being forced into a.

position along the exterior surface of said pin and engaging the lip ofsaid spring iingers with said external shoulder, and means for lockingsaid sleeve in position to hold said spring ngers in said last-namedposition and to hold said lip in engagement with said exterior shouldersto prevent lateral separation of said box and pin.

4. A drill collar, comprising a pin portion and abox portion, anexternal shoulder on said pin portion, a second external shouldermounted on said pin portion longitudinally spaced from said firstmentioned external shoulder on said pin portion, an internal sealpositioned on the wall of said box section and abutting the end of saidmemes pin. an internal shoulder on said box section. a seal between saidlast-named shoulder on the box and the first-named shoulder on said pinsection, mating splines positioned on the walls of said pin and boxsections between said seals, a plurality of spring lingers mounted onsaid box, said spring ngers being normally bowed away from the axis ofsaid box, an overhanging lip formed at the free end of said spring ngerscomplementary to said second external shoulder on said pin, a sleeveslidably mounted over the exterior surfaces of said box and said springngers, said spring fingers being forced into a position along theexterior surface of said pin and engaging the lip of said spring ngerswith said external shoulder, and means for locking said sleeve inposition to hold said spring fingers in said last-named position and tohold said lip in engagement with said exterior shoulders to preventlateral separa- JANIES MOON.

REFERENCES CITED The following references are of record in theV tile ofthis patent:

UNITED STATES PATENTS Number Name Date 1,904,061 Larson Apr. 18, 19332,296,198 Boynton Sept. 15, 1942

